Process of treating petroleum products



Dec. 29, 1936. w, c MERCHANT 2,066,213

PROCESS OF TREATING PETROLEUM PRODUCTS Filed Dec. 6, 1935 Patented Dec. 29, 1936 PROCESS OF TREATING PETROLEUM PRODUCTS William 0. Merchant, Everett, Mass. Application December 6, 1933, Serial No. 701,147 7 2 Claims.

This invention relates to a process of treating petroleum products for the removal of certain impurities therefrom.

In general, the invention has for an object to 5 provide a novel and highly efiicient process of treating petroleum products to desulphurize the same and. to remove gummy constituents therefrom, by which such impurities may be removed to a degree not heretofore commercially possible and without the necessity of employing special agitating equipment of washing operations, thus maintaining at a minimum the equipment investment and enabling superior petroleum products to be produced at minimum expense.

1 With this general object in view and such others as may hereinafter appear, the invention consists in the process of treating petroleum products hereinafter described and particularly defined in the claims at the end of this specifi- 20 cation.

The drawing illustrates diagrammatically the preferred apparatus for practicing the present invention.

At the present time the commercial practice 25 employed in the distillation of crude petroleum in producing gasoline and kerosene includes the treatment of the distillates to remove gummy matter which imparts a yellow and somewhat cloudy appearance to the distillates. This treat- 30 ment has usually involved the agitation of the distillate in special agitating tanks with sulphuric or other acid to remove portions of the gummy matters in the distillate, and after the acid treatment the distillate is washed with a 35 solution of soda. The process is relatively slow and involves the use of rather extensive equipment, and at best only a portion of the gummy material is removed. In addition, it has also been the practice to desulphurize the distillates 40 to a limited extent, and the liquid petroleum within the still and the liquid within the rectifying towers have been treated with certain oxides such as copper oxide, and as a result a small portion of the sulphur content of the distillates 45 has been removed by reaction with such metallic oxides.

In accordance with the present invention a process for treating the products of distillation from crude petroleum such as the gasoline and 50 kerosene distillates is provided by which the gummy matters may be satisfactorily removed without necessity of the special washing processes above referred to and also the sulphur content of the distillates may be substantially all re- 55 moved in a simple, efiicient and practical manner with simple and economically operated equipment. To this end the vapors resulting from the distillation of the crude petroleum or from the distillation of any petroleum product are passed into contact with a desulphurizing agent, pref- 5 erably a metallic oxide such as copper oxide, lead oxide, iron oxide, mercuric oxide, or the like, and during the contact of the vapors with such desulphurizing agent, the vapors are preferably maintained in a superheated condition or 10 at a temperature substantially above the point of saturation, and as a result of the contact of such superheated vapors with the desulphurizing agent such as copper oxide, it has been found that substantially all of the sulphur content is removed from the vapors as well as most of the objectionable gummy matters, which have heretofore imparted cloudiness and characteristic color to the distillates.

Referring now to the drawing, which illustrates more or less diagrammatically suitable apparatus for distilling crude petroleum in accordance with the present invention, [0 represents a container for a source of supply of the crude petroleum or other petroleum product, from which a still I2 may be charged through the supply line 14. The still [2 is illustrated as heated by burners I6 and the vapor products of the distillation are conducted through a vapor line 18 to a rectifying tower 20, and thence to the usual condenser 22 through the line 23. The condensate from the tower 20 may be returned to the still through the usual return line 24. The distillate condensed by the condenser may be received within a receiver 25.

The apparatus as thus far described may be constructed and operated in accordance with usual distilling practice.

In accordance with the preferred process the vapors after leaving the rectifying column are conducted through a contact chamber or retort 30 containing a metallic oxide, and provision is made for heating the retort to heat the vapors to above the saturation point, or, in other words, to a superheated condition while they are contacting the metallic oxide in passing through the retort 30.

In addition to superheating the vapors, the burners 32 herein shown as heating the retort 30 also serve to heat the metallic oxide con tained therein up to a point such as to facilitate the reaction between the sulphur and gummy matter contained in the vapors and the metallic oxide.

In practice I prefer to utilize cuprous oxide and have experienced satisfactory results by forming briquettes using linseed oil as a binder for the cuprous oxide and baking the briquettes. The retort may then be charged with such briquettes and during the passage of the vapors through the retort, they are superheated and substantially all of the sulphur and gummy matter removed therefrom. I also prefer to effect the passage of the vapors through the retort while under pressure and this may be conveniently accomplished by a standard form of choke valve 34 in the line between the retort 30 and the condenser 22.

In producing gasoline substantially free from sulphur and gummy matter in accordance with the present process, I prefer to superheat the vapors to a temperature substantially above 400 F. and in practice prefer to operate the retort 30 so that the vapors are superheated to approximately 525 F. In producing kerosene substantially free from sulphur and gummy matter; I prefer to heat the vapors during their passage through the retort 30 to substantially above 525 F. and preferably in the neighborhood of 600 F. If found advantageous these temperatures may be raised.

The utility of the present process will be apparent by comparison of the gasoline produced in accordance with the agitating and washing process above referred to of the prior art which was found to contain one tenth of one percent sulphur, whereas a similar gasoline produced in accordance with the present process contains 0.028% sulphur. In other words, the sulphur in the present product was reduced to approximately one-quarter of one percent. Similarly,

the gasoline of the prior art contained 10 milligrams of gummy matter per 100 cubic centimeters, and a comparative gasoline produced in accordance with the present process contained only 4.8 milligrams of gummy matter per 100 cubic centimeters.

From the description thus far it will be observed that the present process produces a superior gasoline in a similar and. highly efficient manner, and as compared with the washing processes heretofore employed the equipment investment may be reduced as much as forty percent.

Having thus described the invention, what is claimed is:

1. In a process of treating petroleum distillates, the step which comprises causing the vapors from the distillation of a petroleum product to contact a reagent consisting entirely of cuprous oxide briquetted with linseed oil while the Vapors are in a superheated condition to remove sulphur and gummy matter therefrom.

2. The process of removing sulphur and gummy matter from light normally liquid petroleum distillates, which comprises, passing said distil lates in. vapor phase through a chamber containing a reagent consisting of substantially pure cuprous oxide formed into briquettes with linseed oil as a binder to contact said vapor with said reagent, superheating said vapors and heating said oxide to a temperature between 400 F. and approximately 600 F. while said vapor is in contact with said oxide, and removing and condensing said vapor.

WILLIAM C. MERCHANT. 

